es6怎么修改数组的值

array.splice(index,howmany,item1,.....,itemX)

var arr = [1,2,3,4,5,6,7,8,9,10];
console.log(arr);
//删除
arr.splice(1,2);
console.log(arr);    //打印：[1,4,5,6,7,8,9,10]

var arr = [1,2,3,4,5,6,7,8,9,10];
console.log(arr);
//替换
arr.splice(1,2,'b','c');
console.log(arr);    //打印：[1, "b", "c", 6, 7, 8, 9, 10]

var arr = [1,2,3,4,5,6,7,8,9,10];
console.log(arr);
//添加，如果不删除元素，但是又存在第三个或者3+的参数，就会有添加的功能
arr.splice(1,0,'a','b','c');
console.log(arr);    //打印：[1, "a", "b", "c", "b", "c", 6, 7, 8]

数组名[指定下标值]=新值;

var arr = [1,2,3,4,5];  //声明一个数组
console.log(arr);
arr[0] = 0;  //修改第一个元素，重新赋值为0
arr[2] = "A";  //修改第三个元素，重新赋值为2
console.log(arr);

const newStr = str.replaceAll(regexp|substr, newSubstr|function)

var arr = [3, 5, "-", "9", "-"];
var newArr = [];

var str = arr.toString().replaceAll("-","新");	//数组转字符串并替换所有特定元素

console.log(str);				//3,5,新,9,新
newArr = str.split(",");		//字符串转数组
console.log("newArr",newArr);	
//newArr (5) ["3", "5", "新", "9", "新"]